GAS CHROM ATOGRAPHY (GC)
By: Susila Kristianingrum susila.k@uny.ac.id
Basic Competencies:
USAGE GC
•
The oil (pet roleum)•
The field of essent ial oils•
The field of medicine•
Chemist ry / research•
Pest icideBENEFITS OF USE GC
Fast
Operat ion is simple
Sensit ive (order of ppm, ppt ), mL, mg
The separat ion (resolut ion) high
Qualit at ive and quant it at ive analysisANALYSIS OF CHROM ATOGRAPHY
GAS-LIQUID: PARTITION
GAS-SOLID: ADSORPTION
Qualit at ive analysis: based on chromat ogram peak t hat appearsGas-Solid Chromatography (GSC)
•
M obile phase: gas•
St at ionary phase: non-volat ile solids , st ableFor example: spheron (Grafit e-coal), linden (molecular sieves) porapak, polypak, chromosorb
Gas-Liquid Chromatography (GLC)
•
Terms of t he solid support :1. St able at high t emperat ures
2.Inert , not react ing w it h samples & st at ionary phase
3.The large surface area (grain) 4. Ideal sit uat ion (same size)
•
Examples of solid support :Diat oport , cilit e, chromosorb (G, P, W)
•
Working basis:Gas-Liquid Chromatography (GLC)
•
M obile phase: gas•
St at ionary phases: liquid, t he condit ion: 1. Non volat ile2. Inert & st able 3. Very viscous
Gas-Liquid Chromatography (GLC)
This t ype of st at ionary phase: polar, semi polar, non polar
Examples of polar st at ionary phases: carbowax 20M , PEGA, DEGS,cast orwax, amine 220, versamid 900, PDEAS
Examples of semipolar st at ionary phases: dionilft alat , SE-52 (OV-17)Classificat ion of compounds
POLAR
w at er
Glycol, glycerol alcohol
Oksim
Hydroxy acids est er
Classificat ion of compounds
SEM I POLAR et her
ket one aldehyde
t ert iary amine et c.
• NON POLAR CHCl3
CH2Cl2
aromat ic hydrocarbons olefin hydrocarbons
BASIC SEPARATION
Compounds
Compounds Stationary Stationary Phase
Phase
nat ure
Polar
Polar PolarPolar SolubleSoluble
Non polar
Non polar Non polarNon polar SolubleSoluble
Polar
Polar Non polarNon polar insoluble
Non polar
Non polar PolarPolar insoluble
CHROM ATOGRAM
GAUSS CURVE1. Eddy diffusion and molecular 2. The balance of slow
3. Price K is not fixed
IDEAL chromat ogram 1. Quickly balance 2. No diffusionCOM PONENTS INSTRUM ENTS GC
Carrier gas t ank (+ regulat or)
Place t he sample inject ion
column
det ect orDet ect or
FID Detector
• Basic work: sample + burner gas (H2 + air/O2) burned Ionization occurs: positive ion to
negative electrode, negative ion to positive electrode
• On electrodes occurs: Change Voltage (V)
Change of voltage forwarded to the recorder and produce chromatogram.
• Advantages: highly sensitive (1000xTCD).
TCD Det ect or / Chat aromet er
•
Conditions: t he t emperat ure of t he det ect or must be higher t han column t emperat ure•
Basic principles: Component s w hich have been separat ed from t he column carried by t hecarrier gas on t he filament . Change of filament t emperat ure causes filament resist ance .
TCD Detector / Chatarometer
•
Advantages:1. Does not dest roy t he sample
2. All kinds of compounds can be det ect ed.
